Bolt assembly

ABSTRACT

A bolt assembly for a Gatling gun, which gun has a stationary housing with the conventional elliptical cam track; a rotor assembly a plurality of barrels, adapted to receive a like plurality of said bolt assemblies; includes means for cocking, searing and reseting the firing pin responsive to the longitudinal disposition of the bolt.

United States Patent Charles C. J acolucci Inventors Richmond; Gordon H. Woodford, Essex Center, both of Vt. Appl. No. 868,379 Filed Oct. 22, 1969 Patented Oct. 12, 1971 Assignee General Electric Company BOLT ASSEMBLY 5 Claims, 5 Drawing Figs.

US. Cl 89/12, 42/16 A, 89/185 Int. Cl F41d 7/04 Field of Search 89/12, 13, l85;42/l6, 16.1

[56] References Cited UNlTED STATES PATENTS 125,563 4/1872 Gatling 89/12 502,185 7/1893 Gatling..... 89/12 2,849,921 9/l958 Otto 89/12 3,380,343 4/1968 Chiabrandy et al 89/12 Primary ExaminerSamuel W. Engle Attorneys-Bailin L. Kuch, lrving M. Freedman, Harry C.

Burgess, Frank L. Neuhauser, Oscar B. Waddell and Joseph B. Forman ABSTRACT: A bolt assembly for a Gatling gun, which gun has a stationary housing with the conventional elliptical cam track; a rotor assembly a plurality of barrels, adapted to receive a like plurality of said bolt assemblies; includes means for cocking, searing and reseting the firing pin responsive to the longitudinal disposition of the bolt.

PATENIEBHBHZEJ?! 361L866 sumeurz I NVEN'TOR.

CHARLES C. JACOLUCCI BY GORDON H WOODFORD BOLT ASSEMBLY BACKGROUND OF THE INVENTION 1. Field of the Invention This invention relates to an improved self-cooking, searing and resetting bolt assembly, especially adapted for automatic weapons having a plurality of barrels mounted for rotation about a common axis, popularly known as Gatling guns.

2. Prior Art In US. Pat. No. 125,563, issued Apr. 9, 1872 to R. I. Gatling, there is shown the classic modern revolving battery gun. A stationary housing encloses and supports a rotor assembly which has a plurality of barrels and a like plurality of bolts. Each bolt has its own firing pin and mainspring. Each bolt is traversed longitudinally by a stationary elliptical cam track in the housing. As the bolt is traversed forward, the firing pin is held to the rear by a stationary cam track in the housing and the mainspring is compressed until the bolt and the barrel reach the firing position, at which time the firing pin is seared. A more recent electrically fired gun is shown in U.S. Pat. No. 2,849,921, issued Sept. 2, 1958 to H. McC. Otto. Here the longitudinal movement of the bolt is controlled by a housing cam track, but the firing pin is always biased forward. A yet more recent Gatling gun, disclosed in U. S. Pat. No. 3,380,343, issued Apr. 30, 1968 to R. E. Chiabrandy et al., utilizes a single mainspring mounted externally of the bolt assemblies on the housing.

This invention is an improvement in a type of Gatling gun sometimes called the minigun. The gun conventionally has a stationary housing, and a rotor assembly with a plurality of barrels and a like plurality of bolts, each with its own firing pin and mainspring. The longitudinal movement of the bolt is provided by the conventional housing elliptical cam track. The cocking, searing and resetting of each firing pin is controlled by a respective cam track in the rotor. Obtaining and maintaining dimensional synchronism among the housing cam track, the bolt and the rotor cam track is a major economic concern. In a concurrently filed patent application by John P. Hoyt, Jr., Ser. No. 868,380 there is described and claimed a bolt assembly wherein an internal mechanism controls the cocking, searing and resetting of the firing pin directly responsive to the longitudinal reciprocation of the bolt.

SUMMARY OF THE INVENTION It is an object of this invention to provide a bolt assembly for a minigun utilizing a simple mechanism for cocking, searing and resetting the firing pin, which is a variant of the mechanism of Ser. No. 868,380.

A feature of this invention is the provision of a bolt assembly for a Gatling gun, which gun has a stationary housing with the conventional elliptical cam track, a rotor assembly and a plurality of barrels, adapted to receive alike plurality of said bolt assemblies, each bolt assembly including means for cocking, searing and resetting the firing pin responsive to the longitudinal disposition of the bolt.

BRIEF DESCRIPTION OF THE INVENTION These and other objects, features and advantages of the invention will be apparent from the following specification thereof taken in conjunction with the accompanying drawing in which:

FIG. 1 is a top view in cross section of an embodiment of this invention, showing the bolt assembly in the fired disposition;

FIG. 2 is a side view in cross section of the bolt assembly of FIG. 1, taken along plane ll-lI of FIG. 1;

FIG. 3 is an end view in cross section of the bolt assembly of FIG. 1, taken along plane Ill-III of FIG. 1;

FIG. 4 is an end view in cross section of the bolt assembly of FIG. 1, and taken along plane IV-IV of FIG. 1;

FIG. 5 is a perspective view of a rotor assembly including bolt assemblies of FIG. I.

THE PREFERRED EMBODIMENT A more complete description of a Gatling gun may be had from US Pat. No. 3,380,343, supra, and Ser. NO. 868,380, As seen in FIG. 5, the rotor assembly, 210 includes a rotor body ll2 having a forward head portion 114 with six ports 116 therein to respectively receive six gun barrels 118 with respective chambers 1180. Six longitudinal ribs 120 project radially from the body between the ports and six track elements 122 are respectively boltedto the ribs by studs I24 extending therefrom, and nuts 126. Six bolt assemblies 128 are respectively mounted between immediately adjacent track elements in alignment with respective barrels. A rotor forward gear 130 and a rotor forwardbearing I32 are fixed on the rotor forward head portion. A rotor aft gear 134 and a rotor aft bearing 136 are fixed to the aft end of the rotor body. I

The rotor assembly is joumaled via the forward and aft bearings for rotation in a housing H which has an internal elliptical cam track 138. A guide bar 140 is fixed to the housing and has fingers to direct cartridges 142 from the feeder assembly, not shown, into the extractors of the bolt, and to cam the spent cartridge cases out of the extractors into the ejection chute, not shown. The feeder may be of the type shown in US. Pat. No. 3,333,506, issued to R. W. Henshaw et al. on Aug. 1, 1967.

Each bolt assembly 128 includes a main body portion 44, a head portion 46, a firing pin 48, and a mainspring 50. A stud 52 extends radially from a boss on the main body portion and a cam follower roller 54 is captured thereon by a ring 56. A pair of longitudinal side slots 58 are formed in the main body portion to ride on the rotor track elements. A central longitudinal bore 60 is formed in the main body portion, together with a helical cutout 62. An aft diametral bore 64 extends through the body portion. The head portion 46 includes a pair of longitudinal side slots 68 to ride on the rotor track elements. A helical arm 70 extends aft to ride in the helical slot 62. A central longitudinal bore 72 is formed in the head portion, the forward portion having a cone-shaped reduction 74 and a smaller diameter aperture 76 into the bolt face 78. Two extractor lugs 80 extend forwardly of the bolt face. The bolt face has a ramp relief surface 82 to guide the extractor plate of the cartridges onto the bolt face when the cartridge is fed to the bolt by the feeder. The bolt also has an alignment slot 84 to engage a rib on the guide bar during feeding, and a relief 86 to clear a feeder sprocket, not shown, and a locking lug 87. The undersurface of the head portion has a L-shaped slot 88, extending to the bore 72, having a longitudinal leg 90 and a transverse leg 92. An access hole 94 extends from the upper surface to the bore 72. The firing pin 48 includes a body portion 95 having a central longitudinal blind bore 96, an aft, longitudinally extending diametral slot 98, and a forward diametral bore 100. The mainspring 50 is captured in the bore 96 by a crosspin 102 which has a flat 104 cut thereto. The aft end of the mainspring is seated in the flat and prevents loss of the crosspin. A headed crosspin 106 is disposed through and past the access hole 94 into the bore and extends into the L-shaped slot 88. The slot 98 has one longitudinal sidewall 98L angularly cutout to permit the crosspin 102 to rock therein about the bolt longitudinal axis, and an aft ramp surface 98R. A cone-shaped penetrator 108 extends forwardly from the body portion 95 and has a cylindrical tip 110. In the assembly, the firing pin 48 is disposed in the bores 72 and with the crosspin I06 retaining the head portion on the firing pin, and the crosspin 102 retaining the body portion on the,firmg pm. I

The rotor body also includes a first set of six T-shaped projections 212, a second set of six T-shaped projections 214, and a set of six annular locking recesses 216, all respectively aligned with, or intermediate with, the barrel bores. The edges of the T-shaped projections are aligned with the track elements to provide continuing guide surfaces for the bolts'zas they advance from the track elements towards the barrels. 1

The longitudinal position of each bolt assembly is controlled by the elliptical cam track in the housing into which is disposed the cam follower roller 54 of each bolt assembly. A cycle of operation may be considered to start with the load function. The bolt assembly is in its maximum aft disposition and is adjacent the feeder guide bar. A cartridge is handed off by the feeder sprockets, guided by the guide bar, onto the bolt face 82, where it is held by the extractor lugs 80. The body portion and the head portion are at their maximum mutual separation, with their side slots riding on the track elements. The distal end of the crosspin 106 is in the distal end of the transverse leg 92 of the L-slot 88. The distal ends of the crosspin 102 are captured in the bore 64, and the medial portion is disposed in the aft end of the slot 98. As the bolt assembly is moved forward it carries the cartridge with it until the cartridge is fully seated in the respective chamber of the respective barrel, and the forward edges of the extractor lugs 80 about the rear face of the barrel. Further forward movement of the bolthead portion is now precluded. The cam follower continues to traverse the bolt body portion forward, so that it rides forward on the now stationary firing pin, and the helical slot 62 cams the helical arm around the firing pin, and with it the head portion which rotates within the annular locking recess so that the bolt-locking lug 87 is within the recess, locking the bolt. Concomitantly, the mainspring is progressively compressed as the crosspin 102 is carried forward in the firing pin slot 98. Further movement forward of the cam follower and the body portion continues the compression of the mainspring, rotation into full lock of the bolthead, and further movement of the transverse leg 92 to the position whereat the crosspin 106 is just short of being seared out of the transverse leg 92 into the longitudinal or firing leg 90. Further forward movement of the cam follower sears the pin 106 into the longitudinal leg, 90 releasing the firing pin which shoots forward under the bias of the compressed mainspring. The penetrator 110 projects forward of the bolt face to impact the base of the cartridge. The pin is halted by the pin shoulder 108a abutting the bore shoulder 72a. It will be noted that the forward extension of leg 90 is made longer than the travel of the crosspin 106 to permit venting of any primer gas.

After firing, the cam follower moves aft, carrying the body portion aft, away from the locked head portion, so that the helical cam slot 62 cams the helical cam follower arm 70 and the integral therewith head portion into unlocking rotation. concomitantly, the crosspin 102 which will be riding along surface 98L abuts the ramp surface 98R and the firing pin is cammed aft by the crosspin 102 fixed in aft-moving bolt body to rotate and positively retract the firing pin and its penetrator without stress on the helical slot and arm, and to swing the crosspin 106 into the distal end of leg 92. Concomittantly, the helical slot and arm provide final unlocking rotation of the bolthead portion to unlock the bolt assembly which is not at the extract position. Further aft movement of the cam follower 54 carries the bolt assembly aft together with the spent cartridge case to the full aft position whereat the spent cartridge is ejected, and after further rotation of the rotor assembly, the bolt assembly is ready to receive a fresh cartridge.

Thus, there has been described a self-operating bolt assembly that does not require any mechanism external to the reciprocating bolt assembly to cook, sear or reset the firing pin. Although the invention has been described in an embodiment adapted for use in a Gatling-type, multiple barrel gun, utilizing an elliptical cam for bolt actuation, it is adapted for use in other guns, such as have a single barrel, using other means to provide reciprocation of the bolt assembly. All that is required to cock, sear and reset the firing pin is relative longitudinal motion between the bolthead and the bolt body.

What is claimed is:

l. A gun bolt assembly comprising:

a main body subassembly:

a head subassembly; and

a firing pin subassembly;

said main body subassembly including:

a main body having forward and aft ends,

means for providing longitudinal reciprocation to said body,

a longitudinal bore in said body opening through said forward end,

a helical cam slot, and

a diametral bore;

said head subassembly including:

a head body having forward and aft ends,

a longitudinal bore through said head body,

a helical cam follower arm mating with said helical cam slot,

an L-shaped, diametral, slot having a longitudinal leg and a transverse leg; and

said firing pin subassembly including:

a firing pin having a forward penetrator end disposed in said head body longitudinal bore and an aft end disposed in said main body longitudinal bore,

a longitudinal bore in said pin opening through said aft end,

a diametral, longitudinally extending, slot through said pin, having an aft ramp surface,

a helical mainspring disposed in said firing pin longitudinal bore,

an aft crosspin disposed in and rockable in said firing pin slot, capturing and abutting said mainspring, and ex tending into main body diametral bore, and

a forward crosspin extending radially from said firing pin and extending into said head body L-shaped slot.

2. A gun bolt assembly comprising:

a main body subassembly;

a head subassembly; and

a firing pin subassembly;

said main body subassembly including:

a main body having forward and aft ends,

means for providing longitudinal reciprocation to said body,

a longitudinal bore in said body opening through said for ward end,

a helical cam slot, and

a diametral bore;

said head subassembly including:

a head body having a forward bolt face and extractor lugs,

and an aft end,

a transversely extending locking lug,

a longitudinal bore through said head body,

a helical cam follower arm mating with said helical cam slot,

an L-shaped, diametral, slot having a longitudinal leg and a transverse leg; and

said firing subassembly including:

a firing pin having a forward penetrator end disposed in said head body longitudinal bore and an aft end disposed in said main body longitudinal bore,

a longitudinal bore in said pin opening through said aft end,

a diametral, longitudinally extending, slot through said pin, having an aft ramp surface leading into the aft end surface,

a helical mainspring disposed in said firing pin longitudinal bore,

an aft crosspin disposed in and rockable in said firing pin slot, capturing and abutting said mainspring, and extending into main body diametral bore, and

a forward crosspin extending radially from said firing pin and extending into said head body L-shaped slot.

3. A gun bolt assembly according to claim 2 wherein:

in the feed position said main body and said head body are at a maximum mutual longitudinal separation and are journaled on said firing pin, with said aft crosspin disposed against the longitudinal aft end of said longitudinally extending firing pin slot and the forward crosspin disposed in the distal rid of said transverse leg of said L- shaped slot, and said mainspring is relatively uncompressed;

in the locked and latched position, said main body and said head body are at a relatively closer mutual longitudinal separation with said head body rotated about said firing pin, with said aft crosspin disposed against the longitudinal forward end of said longitudinally extending firing pin slot and said forward crosspin disposed in said transverse leg of said L-shaped slot closely adjacent to said longitudinal leg, and said mainspring is compressed;

in the seared position, said main body and said head body are at a minimum mutual longitudinal separation with said head body further rotated about said firing pin, with said aft crosspin disposed against said longitudinal aft end of said longitudinally extending firing pin slot and said forward crosspin disposed in said longitudinal leg of said L-shaped slot, with said penetrator of said firing pin extending forward of said head body face.

4. A gun bolt assembly according to claim 3 wherein:

during the extraction and reset functions, said aft ramp surface is cammed relatively aft along said aft erosspin to positively withdraw said penetrator aft into said head body, and relatively rotated to swing said forward crosspin into said distal end of said transverse leg of said L- shaped slot.

5. A multibarreled gun comprising:

a housing having an interior elliptical cam groove;

a rotor assembly, joumaled for rotation within said housing,

including:

a rotor body having a plurality of barrel-receiving ports in an annular row, and a like plurality of bolt-receiving guideways respectively aligned with said port, including an annular locking recess adjacent said port, and

a like plurality of bolt assemblies, respectively disposed in said guideways,

each bolt assembly comprising: a main body subassembly; a head subassembly; and

a firing pin subassembly; said main body subassembly including:

a main body having forward and aft ends,

cam follower means disposed in said housing cam groove for providing longitudinal reciprocation to said body,

a longitudinal bore in said body opening through said forward end,

a helical cam slot, and

a diametral bore;

said head subassembly including:

a head body having forward and aft ends,

a longitudinal bore through said head body,

a helical cam follower arm mating with said helical cam slot,

an L-shaped, diametral, slot having a longitudinal leg and a transverse leg, and

a transversely extending locking lug adapted, upon rotation of said head body, to enter said guideway-locking recess;

said firing pin subassembly including:

a firing pin having a forward penetrator end disposed in said head body longitudinal bore and aft end disposed in said main body longitudinal bore,

a longitudinal bore in said pin opening through said aft end,

a diametral, longitudinally extending slot through said pin, having an aft ramp surface leading into the aft end surface,

a helical mainspring disposed in said firing pin longitudinal bore,

an aft crosspin disposed in and rocable in said firing pin slot, capturing and abutting said mainspring, and extending into main body diametral bore, and

a forward crosspin extending radially from said firing pin and extending into said head body L-shaped slot.

l0l005 009l 

1. A gun bolt assembly comprising: a main body subassembly: a head subassembly; and a firing pin subassembly; said main body subassembly including: a main body having forward and aft ends, means for providing longitudinal reciprocation to said body, a longitudinal bore in said body opening through said forward end, a helical cam slot, and a diametral bore; said head subassembly including: a head body having forward and aft ends, a longitudinal bore through said head body, a helical cam follower arm mating with said helical cam slot, an L-shaped, diametral, slot having a longitudinal leg and a transverse leg; and said firing pin subassembly including: a firing pin having a forward penetrator end disposed in said head body longitudinal bore and an aft end disposed in said main body longitudinal bore, a longitudinal bore in said pin opening through said aft end, a diametral, longitudinally extending, slot through said pin, having an aft ramp surface, a helical mainspring disposed in said firing pin longitudinal bore, an aft crosspin disposed in and rockable in said firing pin slot, capturing and abutting said mainspring, and extending into main body diametral bore, and a forward crosspin extending radially from said firing pin and extending into said head body L-shaped slot.
 2. A gun bolt assembly comprising: a main body subassembly; a head subassembly; and a firing pin subassembly; said main body subassembly including: a main body having forward and aft ends, means for providing longitudinal reciprocation to said body, a longitudinal bore in said body opening through said forward end, a helical cam slot, and a diametral bore; said head subassembly including: a head body having a forward bolt face and extractor lugs, and an aft end, a transversely extending locking lug, a longitudinal bore through said head body, a helical cam follower arm mating with said helical cam slot, an L-shaped, diametral, slot having a longitudinal leg and a transverse leg; and said firing subassembly including: a firing pin having a forward penetrator end disposed in said head body longitudinal bore and an aft end disposed in said main body longitudinal bore, a longitudinal bore in said pin opening through said aft end, a diametral, longitudinally extending, slot through said pin, having an aft ramp surface leading into the aft end surface, a helical mainspring disposed in said firing pin longitudinal bore, an aft crosspin disposed in and rockable in said firing pin slot, capturing and abutting said mainsprIng, and extending into main body diametral bore, and a forward crosspin extending radially from said firing pin and extending into said head body L-shaped slot.
 3. A gun bolt assembly according to claim 2 wherein: in the feed position said main body and said head body are at a maximum mutual longitudinal separation and are journaled on said firing pin, with said aft crosspin disposed against the longitudinal aft end of said longitudinally extending firing pin slot and the forward crosspin disposed in the distal nd of said transverse leg of said L-shaped slot, and said mainspring is relatively uncompressed; in the locked and latched position, said main body and said head body are at a relatively closer mutual longitudinal separation with said head body rotated about said firing pin, with said aft crosspin disposed against the longitudinal forward end of said longitudinally extending firing pin slot and said forward crosspin disposed in said transverse leg of said L-shaped slot closely adjacent to said longitudinal leg, and said mainspring is compressed; in the seared position, said main body and said head body are at a minimum mutual longitudinal separation with said head body further rotated about said firing pin, with said aft crosspin disposed against said longitudinal aft end of said longitudinally extending firing pin slot and said forward crosspin disposed in said longitudinal leg of said L-shaped slot, with said penetrator of said firing pin extending forward of said head body face.
 4. A gun bolt assembly according to claim 3 wherein: during the extraction and reset functions, said aft ramp surface is cammed relatively aft along said aft crosspin to positively withdraw said penetrator aft into said head body, and relatively rotated to swing said forward crosspin into said distal end of said transverse leg of said L-shaped slot.
 5. A multibarreled gun comprising: a housing having an interior elliptical cam groove; a rotor assembly, journaled for rotation within said housing, including: a rotor body having a plurality of barrel-receiving ports in an annular row, and a like plurality of bolt-receiving guideways respectively aligned with said port, including an annular locking recess adjacent said port, and a like plurality of bolt assemblies, respectively disposed in said guideways, each bolt assembly comprising: a main body subassembly; a head subassembly; and a firing pin subassembly; said main body subassembly including: a main body having forward and aft ends, cam follower means disposed in said housing cam groove for providing longitudinal reciprocation to said body, a longitudinal bore in said body opening through said forward end, a helical cam slot, and a diametral bore; said head subassembly including: a head body having forward and aft ends, a longitudinal bore through said head body, a helical cam follower arm mating with said helical cam slot, an L-shaped, diametral, slot having a longitudinal leg and a transverse leg, and a transversely extending locking lug adapted, upon rotation of said head body, to enter said guideway-locking recess; said firing pin subassembly including: a firing pin having a forward penetrator end disposed in said head body longitudinal bore and aft end disposed in said main body longitudinal bore, a longitudinal bore in said pin opening through said aft end, a diametral, longitudinally extending slot through said pin, having an aft ramp surface leading into the aft end surface, a helical mainspring disposed in said firing pin longitudinal bore, an aft crosspin disposed in and rocable in said firing pin slot, capturing and abutting said mainspring, and extending into main body diametral bore, and a forward crosspin extending radially from said firing pin and extending into said head body L-shaped slot. 